Multicompartment containers for medical solutions are frequently used. Particularly in case the medical solution comprises a mix of one or more single solutions that are incompatible during sterilization or storage and thus have to be separated. For instance a single solution that contains glucose should be kept separate from substances that catalyze the glucose degradation and also kept at a low pH to further stabilize the glucose molecule. Another example is that a single solution containing bicarbonate or phosphate should be kept separated from a single solution containing calcium or magnesium in order to avoid precipitation. A further example is that a diluent and a medicament need to be maintained separate. Still a further example is that a single solution with high pH needs to be maintained separate from a single solution with low pH.
The medical solution used by a patient should always be physiological upon delivery to the patient as well as a medicament should be at correct concentration. For this reason it is of importance that the single solutions are always safely mixed before delivered through an outlet to the patient. In case one of the above-exemplified single solutions is delivered unmixed with the other single solution it may be hazardous to the patient.
The need to keep single solutions of a medical solution separate in compartments of a multicompartment container is recognized in the area of containers for administration of sterile or non-sterile medical solutions in chemical or drug therapies, for nutritional supplements, for apheresis, for parenteral administration, or for renal therapies e.g. hemodialysis, hemodiafiltration, hemofiltration or peritoneal dialysis.
An example of a flexible multicompartment solution container is known from U.S. Pat. No. 5,176,634. U.S. Pat. No. 5,176,634 discloses a container where separate compartments in the container are formed by frangible heat seals. A first compartment contains a liquid diluent; a second compartment contains a powdered medicament, which may be mixed with the liquid diluent by separating the frangible seal dividing the first and the second compartment. Separating of the seal is accomplished by manipulating the container to create pressure on the diluent in the first compartment, which then hydraulically separates the seal between the first and the second compartment allowing the diluent and medicament to be mixed. A third compartment adjacent the second compartment and opposite from the diluent compartment contains an outlet port for dispensing the mixed solution. A seal between the second and the third compartment prevents administration of the contents before mixing of the contents of the first and the second compartment. After mixing, additional manipulation of the container to exert pressure on the contents ruptures the second seal allowing the medicated solution to be dispensed through the port. Where a liquid medicament is used, the relative size between the diluents compartment and the medicament compartment and the placement of the smaller compartment intermediate to the larger compartment and the lower or outlet compartment assures development of hydraulic forces which will rupture the seal between the diluent and medicament compartments before rupture of the second seal with minimal care.